1. Field of the Invention
The current invention relates to a vehicle, particularly a railway vehicle, comprising a longitudinal axis, a first superstructure, a second superstructure that adjoins the first superstructure in the direction of the longitudinal axis of the vehicle, and a pitch joint, which connects the first superstructure and the second superstructure. It also relates to a corresponding pitch joint for an inventive vehicle.
2. Description of Related Art
In the case of railway vehicles, but also with other vehicles, pitch joints are used if wagon parts, for example vehicle bodies (superstructures), are connected by means of floating joints on a multiple-unit articulated train and, when traveling over rises or troughs, a pitch possibility is necessary on this articulated connection, i.e., the possibility of swiveling around a transverse axis of the vehicle that normally runs essentially horizontal.
In the area of the undercarriage, the wagon parts are normally connected by a lower joint. This lower joint typically permits the following relative movements of the wagon parts within certain limits: rotation around a vertical axis of the vehicle (Z axis), commonly called pivoting, and rotation around a transverse axis of the vehicle (Y axis), commonly called pitching. Depending of the type of this lower joint, rotation around the vehicle longitudinal axis (X axis), commonly called rolling, can also be permitted, if necessary.
When traveling into a curve, the individual wagon parts experience different roll positions within a multiple-unit vehicle. Depending upon the design of lower joint, these cause great side sway between the individual wagon parts or high torsional stress to the lower bearings. For this reason, the wagon parts are mutually supported in the region of the roof structure by an additional transverse connection, which is also designated as a roll support among other things. In this case, it is typically a transverse control arm or a sliding block guide coupled to both wagon parts and extending in the transverse direction of the vehicle.
However, there are a series of disadvantages with these solutions. When traveling on curves, with the normally off-center positioning of the transverse control arm, the inside-curve bearing approaches the adjacent wagon part so that, in the case of tight curves, it is possible for the wagon parts to intersect, i.e., collide. In just the same way, when there is a rigid control arm and during travel over rises or troughs, the distance between the outside bearings and the vertical axis of the vehicle (Z axis) changes thereby producing forced twisting of the superstructures. The disadvantage of the normal sliding block guides is that the sliding block approaches the adjacent wagon part during travel over rises and troughs As a result, the wagon parts may intersect, i.e., collide, when there are changes of gradient.